eActivity is the rewards program for active eCredits users. eActivity (ACT), are not equivalent to ECS, but they are earned for certain activities: 

For example, when you use eCredits for daily shopping or when you invite a friend to create an eCredits account, you are rewarded. The more you use the eCredits Wallet App, the more eActivity you earn. 

eActivity is not a cryptocurrency, and eActivity are earned through participation, being an active user of eCredits.